Telemetric system



Nov. 9, 1948. H. 'r. HOFFMAN 2,453,686 TELEMETRIC SYSTEM Filed Oct.25,1947

. al JE I E INVENTOR.

3 HOWARD T. HOFFMAN BY r cow Patented Nov. 9, 1948 to Bailey Meter ComDelaware many, a corporation Application-October 25, 1947, Serial No.782,113

This invention relates-to telemetric' systems, and more particularly totelemetric systems in which a; receiver is adapted to operateperiodically in response to signals from a transmitter and adjust areceiving or indicating member until it.

is in correspondence with a transmitting member.

A preferred embodiment of my invention may.

include motors operating in response to transmitted signals andcontrolling circuits of another motor which positions a receiving orindicating member. Changes in position of the receiving member regulatesthe control effected by the first motors in such a manner thatoperationsv of the motor positioning the receiving member isreduced'asit is brought intocorrespondence with the transmitting member.When the two members are in exact correspondence, the control is soregulated that no operation of the indicator motor is obtained.

An object of my invention is to provide an improved telemetric system.Another object is to provide a telemetric system having a receiveradapted f or operation in response to signals transmitted at a lowvoltage-by a transmitter. Still another object is to provide in animproved telemetric system a receiver having means operating in responseto transmitted signals and under the control of a receiving member forregulating the position of the latter. Other objects will appear in thecourse of the following description.

In the accompanying drawing there is shown for purposes'of illustrationa schematic diagram of my improved telemetric system.

Referring to the drawing it will be noted that there is shown atransmitter I and a receiver 2, the transmitter having a pivotedtransmitting member 3 which is positioned in response to changes in somevariable condition, and the receiver having a receiving or indicatingmember 4' adapted to be moved to positions corresponding with those ofthe transmitting member. A suitable device 6, such as a Bourdon tube, isoperatively connected to the transmitting member for positioning thelatter in response to changes in some variable condition, such aspressure or temperature in a conduit 1. Scales 8 and 9 are showncooperating with the transmitting and receiving members respectively toprovide a reading of the changes in the condition. A pivoted contactorI0 is operatively engaged by the transmitting member so as to bepositioned by the latter. The transmitter is also provided with aconstant speed motor I! driving a substantially uniform rise cam l4 inthe direction of the arrow. A pivoted contactor I engages the peripheryof the cam 12 Claims. (Cl. 318-18) 14 and is periodically reciprocatedby the latter to engage the contactor it during time intervals varyingwith the positions of the contactor l0 determined by the member 3. Atthe receiver is a relay having a winding i'l connected at one end by aconductor it to one side of a D. C. source, and connectable at its otherend through a-conductor, it, the contactors l3,

' l5, and a conductor 20 to the other sideoi the D. C. source. A relayarmature 22 carries a contact arm 24 engageable with one or the other ofa pair of contacts 2 1-, 28 for controlling an cults shortly to bedescribed.

The receiving member 4 is shown diagrammati .cally arranged to bepositioned by a reversible motor having shading poles 30, 3|, and afield winding 32 continuously energized from a source of alternatingcurrent. Rotation of the motor in one direction is effected by shortcircuiting the pole winding 30, while rotation in the opposite directionis efiected by short circuiting the winding 3|. If the pole windings areboth open circuited or both short circuited, the motor remainsstationary and is not urged to rotation in either direction. Theadjacent ends of the pole windings are connected by a. common conductor33 and 'branch conductors 34, 35 to stationary contacts 36 and 31, andthe other ends of the pole windings 30, 3| are connected respectively byconductors 38, 39 to contactors 40, 4|. engageable with the contacts 36and 31, respectively, and normally assuming positions out of engagementwith such contacts.

- When the contactor 40 is forced into engagement with contact 36, acircuit is completed short circuiting the pole winding 30 so as toeflect an operation of the motor to swing the receiver 3| and anoperation of the motor to swing the receiving member in acounterclockwise direction. Movement of the contactors 40, 4| intoengagement with the contacts 36, 31 is accomplished by constant speedmotors 4'5, having windings 41, 48 connected at one end to a conductor50 leading to a source of alternating current, and connected at theirother ends to conductors 5|, 52 leading to the contacts 27, 28. Thecontact arm 24 is connected by a conductor 54 to the source ofalternating current and operates on engagement with contact 21 or 28 tocomplete a circuit for energizing the winding 4'! or the winding 4LOperatively connected to the motors 45, 46 are members 56, 51 normallyheld by springs 58, 59 in engagement with abutment portions 60, 6|carried by the receiving member 4, and the members *56, 51 are adaptedto be moved by the motors into engagement with the contactors 40, 4| forforcing the latter against the contacts 36, '31. The abutment portions60, 6| are so spaced that the time required by the motor 45 to move themember 56 from the abutment 66 to a point where it forces the contactor40 into engagement with the contact 36 plus the time required by themotor 46 to move the member 51 from the abutment 6| to a point where itforces the contactor 4| into engagement with the contact 31 equals thetime required for the cam 54 to make one complete revolution. The cam I4is of such shape that the time intervals during which the contactors I6and I5 are engaged and disengaged when the transmitting member 3 is inthe position shown, are equal.

The operation of the mechanism described is as follows:

The cam i4 is shown moving the contactor i5 towards the contactor illwith only a short distance remaining to travel before engagement betweenthe contactors isicompleted. With the contactors disengaged, the relaywinding ii is deenergized and the armature 22 is in such a position thatits contact arm 24 engages the contact 28 and completes the circuitthrough the motor winding 48, causing the motor 46 to operate and swingthe member 51 towards the contactor 4|. With the receiving member 4 incorrespondence with the transmitting member as shown, the member 51 4|with contact 371 just as the cam l4 moves the contactor l5 intoengagement with the contactor I0. Closing of contactors l6 and i5energizes the relay winding ii to move the armature 22 to such aposition that the contact arm 24 engages the contact 2'5. A circuit isthen completed from the source of alternating current through theconductor 54, the contact arm 24, the contact 2i, conductor 5|, motorwinding 41 and conductor 56 to effect operation of the motor 45 in adirection to move the member 56 towards the contactor 46. Movement ofthe contact arm 24 away from the contact 28 results in a deenergizing ofthe motor winding 48 and a repositioning of the member 51 against theabutment portion 6| by the spring 59. By the time that the motor 45moves the member 56 to a position to connect the contactor 46 with thecontact 36, the cam M will be in a position to permit contactor l5 tomove away from contactor I and deenergize the relay winding N. Thisresults in a deenergization of the motor winding 41 so that the member56 is returned to the abutment portion 66 by the spring 56, and anenergizing of the motor winding 48 to move the member 51 towards thecontactor 4i.

If the condition changes so that the transmitting member 3 is actuatedto move the contactor ID to a position spaced further from contactor l5,it will be seen that the time periods during which the contactors l6 andi are disengaged and engaged will be correspondingly increased anddecreased, respectively. The increased period of'disengagement betweenthese contactors will result in a holding of contact arm 24 inengagement with contact 28 for a time after the member 51 has been movedfrom the abutment portion 6| in the position shown, to a point where itholds the contactor 4! in engagement with the contact 31. This completesa circuit from the contact 31 through the conductors 35, 33, the polewinding 3|, and the conductor 36 to the conwill reach a point to closecontactor tactor 4|, thereby short circuiting the pole winding 3| andeffecting operation of the motor to move the receiving member 4 in acounterclockwise direction. The abutment portions 66 and 6| are movedwith the receiving member to decrease and increase, respectively, thedistances of travel required by the members 56 and 51 to engage thecontactors 40 and 4|. When the contactor I5 is finally moved intoengagement with the contactor Hi, the member 56 will be moved by themotor from its position nearer to contactor 40, towards the latter. Ifthe time required to move the member 56 to a position engaging contactor46 with contact 36 is less than the time period during which contactorsl0 and I5 are held closed, then a circuit will be completed from thecontact 36 through the conductors 34, 33, pole winding 30, and theconductor 38 to the contactor 40, thereby short circuiting the winding3|! and effecting operation of the motor to position the receivingmember 4 in a clockwise direction. As soon as the member 4 reaches aposition in correspondencewith the new position of the transmittingmember 3, the travel distances for the members 56 and 51 will beadjusted so that they reach points to actuate the contactors 40 and 4|just as the contactors i6 and I5 are being opened and closed. A changein the position of the transmitting member 3 to position the contactorl0 nearer to the contactor l5 results in an operation of the motor toposition the receiving member 4 in a clockwise direction from theposition shown, thereby increasing and decreasing the travel required bythe members 56 and 51, respectively.

While there is described in this application one form which my inventionmay assume in practice, it will be understood that the invention may bemodified and embodied in various other forms without departing from itsspirit or the scope of the appended claims.

What I claim as new and desire to secure by United States Letters Patentis:

1. A telemetric system comprising, in combination, a transmitteroperating to transmit a signal during portions of fixed time periods,said partions varying directly with changes in a variable, a receiverincluding a movable receiving member, a reversible motor for positioningsaid receiving member, circuits operable selectively for energizing saidmotor to eifect its operation in one direction or the other, controlmembers movable towards and away from positions for closing saidcircuits, abutments movable with said receiving member and engageable bysaid control members for limiting movement of the latter away from theircircuit closing positions, means for yieldingly holding said controlmembers in engagement with said abutments, motors for moving saidcontrol members from said abutments toward their circuit closingpositions, means operating in response to said transmitted signal forenergizing one of said motors, and means operating on the termination ofsaid signal for ener izing the other of said motors.

2. The system of claim 1 in which a closing of either one of saidcircuits effects operation of said reversible motor in a direction toposition said abutments so as to increase the travel distance requiredby the one of said members operating to close the circuit. 4

3. A telemetric system comprising, in combination, a transmitteroperating to transmit a signal during portions of fixed time periods,said portions varying directly with changes in a variable condition, areceiver including a movable re- H of said circuits, and means 7receiving member for regulating the time periods oi operation'requiredby each of said last two said celving member, a reversible motor havingopposed shading poles and operable to position said receiving member,circuits operable selectively for short .circuiting one or the other ofsaid shading poles to effect operation of said motor in one direction orthe other, control members movable towards and away from positions forclosing said L 1 circuits, abutments movable with said receiving memberand engageable by said control members ior limiting movement of thelatter away from their circuit closing positions, means for yieldinglyholding said control members in engagement with said abutments,-meansoperating'in I response to said transmitted'signals' for moving one ofsaid control members at a constant speed toward its circuit closingposition, and means operating on termination of said signal for movv ingthe other of said members at a constant speed toward its circuit closingposition. 4. A telemetric system comprising, in combination, atransmitter operating to transmit a signal during portions of fixed timeperiods, said portions varying directly with changes in a variable, areceiver including a movable receiving -rnernb'er, a reversible motorfor" positioning said receiving member, circuits operable selectivelyfor energizingsaid motor to eflect its operation in one direction or theother, means operating during the transmission of said signal forcompleting one of said circuits, means operating during the absence ofsaid signal for completing the other adjustable by said mentioned meansto complete said circuits.

5. A telemetric receiver comprising, in combination, a movable receivingmember, a reversible motor for positioning said receiving member,circuits operable selectively for energizing said motor to effect itsoperation in one direction or the other, means operating during timeperiods proportional to transmitted signals for completing saidcircuits, and means adjustable by said receiving member for regulatingthe time periods of operation required by said means to complete saidcircuits.

6. A telemetric receiver comprising, in'combination. a movable receivingmember, a reversible motor havingopposed shading poles and operable toposition said receivin member, means including contactors normally heldin open positions and operable to short circuit said shading poles,members for actuating said contactors, abutments carried by saidreceiving member and engageable by said members for limiting movement ofthe latter away from said contactors, yielding means said members inengagement with 's'aidabutments, motors for'moving said members fromsaid abutments toward said contactors, and

means operating in response to transmitted signals for controlling theenergizing of said motors moving said members. I

8. A telemetric receiver comprising, in combination, a movable receivingmember, a reversible motor for positioning said receiving member, cir-'-cuits for energizingsaid motor to effect its operation in one, directionor the other, said circuits including contactors normally held in openpositions, means including constant speed motors for closing saidcontactors, means responsive to,

transmitted signals for effecting consecutive energization of saidconstant speed motors, and

means adjustable with said receiving member for varying the operationrequired by said constant speed motors to effect a closing of saidcontactors.

9. A telemetric receiver comprising, in combination, a movable receivingmembenareversible motor for positioning said receiving member, circuitsfor energizing said motor to effect its operation in one direction orthe other, said circuits including contactors normally held in openpositions, means including constant speed motors for closing saidcontactors, means operating inresponse to transmitted signals foreffecting cona to transmitted signals for energizing the other 01" saidconstant speed motors, and means adjustable with said receiving memberfor varying the operation required by said constantspeed motorstobi'nation, a movable receiving member, a reversible sec'utiveenerglzation of said constant speed motors, and means adjustable withsaid receiving member for increasingthe operation required, by one ofsaid constant speed motors and'decreasing the operation requiredby theother of said constant speed motors, toeflect a closing of saidcontactors.

10. A telemetric receiver comprising, in combi-' nation, a movablereceiving member, a reversible motor for positioning said receivingmember, circuits for energizing said motor to eil'ect its operation inone direction orthe other, said circuits in- I eluding contactorsnormally held in open positions, means including constant speed motorsforclosing said contactors, means vincluding a relay normally held in aposition to energize one of said constant speed motors and operating inresponse effect a closing of saldcontactors.

'11. A telemetric receiver comprising, in commotor for positioning saidreceiving member, circuits for energizing said motor to eiIect itsoperation in one direction or the other, said circuits includingcontactorssiormally held in open posimotor for positioning saidreceiving member, circuits operable selectively for energizing saidmotor to effect its operation in one direction or the other, a contactorincluded in each of said circuits and normally held in an open position.

tions, means including constant speed motors for moving said contactorstoward circuit' closing positions, means normally energizing'one of saidconstant speed motors and operating inresponse to transmitted signalsfor energizing the other or said constant speed motors, and meansmovable with said receiving member for varying inversely the travelrequired by said contactors to reach circuit closing positions.

i 12. The receiver of claim 11 in which said last mentioned means movesso as to increase the members for moving said contactors toward their.

closed positions, abutments movable with said receiving member andengageable by said members for limiting movement of the latter away frommeans for yieldingly holding travel distance required by the'contactor'then closing a circuit for energizing said reversible motor and todecrease the travel distance required by the other of said contactors.

' HOWARD T; HOFFMAN.

' No references cited.

